1. Field of the Invention
The present invention relates to a pressure regulator with gauge embedded handle in which a secondary fluid pressure is set by manipulating a handle having a cylindrical portion, and a pressure gauge is disposed in the handle.
2. Description of the Related Art
[Japanese Utility Model Document 1 and Japanese Patent Document 1]
Japanese Utility Model Document 1 (H04-45043) and Japanese Patent Document 1 (JP-A-2001-5534) disclose the pressure regulator in which a valve chamber is disposed between a primary port (supply port) and a secondary port (output port), a main valve body (supply valve body) in the valve chamber is biased toward a main valve seat (supply valve seat) by a valve spring (return spring), the main valve body is biased away from the main valve seat by a pressure adjustment spring mounted between a feedback member (diaphragm) and a pressure adjustment spring retainer, a pressure gauge is disposed in a handle having a cylindrical portion, a feedback chamber between the feedback member and the valve chamber is in communication with the pressure gauge via a pressure introduction communication passage, and the handle adjusts an axial position of the pressure adjustment spring.
In the related art 1 (Japanese Utility Model Document 1), to almost perfectly prevent the pressure gauge from rotating relative to a bonnet of the valve main body even when the handle is rotated, a polygonal guide rod of a lower portion of an mount member is engaged with a polygonal hole at a lower end of a pressure adjustment nut which does not rotate relative to the bonnet, so that the mount member is connected to, but does not rotate relative to the pressure gauge. However, the machining cost of this guide rod is quite costly. Additionally, there is a slight clearance between the guide rod and the polygon-shaped hole. When a rotational direction of the handle is reversed, an angle is generated due to the slight clearance at the beginning of the reversal, and the pressure gauge rotates by the angle in a rotational direction of the handle. After that, the pressure gauge does not rotate even when the handle rotates. In other words, the pressure gauge rotates slightly relative to the bonnet at the beginning of the reversal, and this relative rotation is conducted to the handle to provide vibration to hands.
In the related art 1 , an introduction passage, through which a pressure in the feedback chamber is introduced to the pressure gauge, is comprised of a pressure introduction hole and a passage, the hole running from a feedback chamber to inner walls of the valve body and bonnet, the passage running in the pressure adjustment screw, mount member, and pressure gauge guide. To airproof the passage from the pressure introduction hole to the pressure adjustment screw and the passage from the mount member passage to the pressure gauge guide, two O-rings need to be disposed between an inner peripheral surface of the bonnet and an outer peripheral surface of the pressure adjustment screw, and two O-rings need to be disposed between an inner peripheral surface of the pressure adjustment screw and an outer peripheral surface of the mount member. Additionally, one O-ring needs to be disposed between an outer peripheral surface of the pressure gauge guide and an inner peripheral surface of the hole of the mount member. Accordingly, the friction when the handle is rotated becomes large to require a large force for manipulating the handle.
In the related art 2 (Patent Document 1), as not described clearly, an indicator, a scale plate, and a pressure range indicator are provided for the pressure gauge. The pressure range indicator is mounted movably to be held at a desired position. A pressure gauge cover is fixed to the pressure gauge. The indicator, scale plate, and pressure range indicator are covered by the pressure gauge cover. Because the pressure gauge cover is fixed to the pressure gauge, and mounted in the handle, it cannot be detached when the pressure gauge is in the handle. Accordingly, to move the pressure range indicator, the pressure gauge needs to be taken out from the handle, and disassembled to detach the pressure gauge cover.